TRUK—SOUTH SEA MYSTERY BASE
By BERTRAM VOGEL
When two unescorted Marine PB4Y’s took off on 4 February 1944 on a daring 2,000-mile reconnaissance mission over Truk, United States military leaders in the Pacific area held their breath in anticipation of what the photographs would reveal. For Truk was then the mystery base of the Pacific, a Japanese bastion reputedly stronger than anything between Pearl Harbor and Japan itself, and it constituted one of the chief obstacles to the United States Navy’s drive against the enemy.
For Truk, of course, the role of mystery base was nothing new. Indeed, it had been enveloped in mystery ever since the Japanese had gained control of it in 1914, and the long and bitter Japanese fight for it at the Versailles Conference in 1922 had not only enhanced its importance but had served as an indisputable index to Japanese intentions in the Pacific. For although Japan held the island group as a mandate, foreign observers were deliberately kept at a distance, and during the 30’s in Japan even the mere mention of Truk by a Westerner was regarded as tantamount to spying. Thus it was only natural that Japanese secrecy should have aroused American suspicion, and soon the word got around: Truk was Japan’s Pearl Harbor.
But it was one of Japan’s best kept secrets of the era, for in reality the Japanese had done almost nothing to fortify Truk. Thus, for example, when Vice Admiral Shigeru Fukudome, erstwhile Chief of Staff of the Japanese Combined Fleet, was questioned about Truk during a post-war interrogation in Tokyo, he found it hard to keep a straight face.
“The defense of Truk in 1943 was extremely weak, and I believe it could have been easily taken,” was the way he put the matter. “The strengthening of the defense there began after that, commencing in 1944. There was no Army force there and the Navy force consisted of a land party with not more than 1,000 men. The fleet, of course, was there, but since it was without carrier air force worth mentioning, had the landing been undertaken there, the fleet would have been either destroyed or would have had to flee. The situation was that everything possible had been sent to Rabaul; it [Truk] was virtually empty.”
What had long been regarded as Japan’s ace up her sleeve had proved to be nothing more substantial than a good poker face on the part of her military leaders—without the ace and without the sleeve. The simple fact was that we had permitted our own military efficiency and reason to serve as a criterion for our evaluation of the enemy. It was one of the grimmest jokes of the war.
Actually, the Japanese Army and Navy, in their typical near-sighted manner, had considered Truk all along as merely a defensive installation and had never, for example, even intended to make use of it as a major repair base for the fleet. And yet the Truk group, 245 islands in a lagoon forty miles in diameter, is one of the most remarkable anchorages and natural fortifications in the world.
The coral reef which encompasses the lagoon is approximately 140 miles in circumference and has only five navigable passes, each one protected by a high island. Stone cliffs hundreds of feet high are an additional natural barrier in the most desirable places, and the treacherous passes, complicated by jagged coral beds and peculiar sea swells, are dangerous even to small craft unmanned by personnel familiar with their nature. But the lagoon itself was capable of sheltering the entire Japanese fleet. Had the Japanese merely constructed drydocks, piers, large repair shops, and good power plants, they would have had a magnificent naval installation.
Japanese reasoning, however, was based along different lines, and for a time it proved to be adequate. Their naval policy was to allot the limited funds at their disposal to the construction of the fleet itself and to cut all other expenditures to the very bone. Such a policy may be sound for a small and generally unpretentious nation—but not for one which seeks to wage global war against the United States. And our own naval antagonists notwithstanding, it is even less sound for a nation as dependent upon sea power as is ours. At any rate, Japan was soon to perceive its tragic mistake.
Since the Japanese Navy had established Truk only as an anchorage and not as a first-class repair base, even during the war there were no piers which could provide for large ships, and the limited number of cranes made it necessary to transfer material from ship to shore and from shore to ship in crude sampans and small craft. Prior to Admiral Spruance’s carrier strike against Truk in February, 1944, only fifty sampans and fourteen tugs were available for the staggering task at hand, and repair capacity was limited to provision for two destroyers and five or six subchasers at a time. To an American naval officer accustomed to the high efficiency of his own service it must seem incredible, but it is a fact nevertheless that for extensive battle repairs the Japanese sent their ships home to Yokosuka or Kure. The seventy repair shops and the single 2,500-ton floating drydock at Truk simply could not do the job. It was inefficiency and waste of the most flagrant sort.
Truk’s defenses "were, if anything, even more ludicrous than its facilities for repair and service. As of the beginning of the war, the Fourth Fleet, which had been organized two years earlier and which was responsible for the defense of Truk, had only four twin-mount dual purpose AA guns, all 12.7 cm. in calibre. Six five-inch coastal guns which were relics of the nineteenth century and the Sino-Japanese War protected the beaches of three of the islands, and eleven 80 mm. guns guarded the pass entrances. Two additional 80 mm. AA guns and some machine guns on Fefan and Eten Islands completed Truk’s defensive armament. And even some of those were later removed and shipped to Rabaul for use there. To man the guns, the Fourth Fleet was first assigned 850 men, later an additional 610 men.
When the American Fifth Fleet and the Marine Second Division began to blast away at Tarawa, however, the Japanese Imperial General Staff, which had been blissfully enjoying its lethargy in Tokyo until then, was finally aroused from its deep dream of peace and contentment. Accordingly, in January, 1944, it re-organized the 52nd Division on Saipan (the division had been mobilized in Japan late in 1943 for duty in the Eastern Carolines) and dispatched half of it to Truk. Pillboxes and beach defenses were hastily erected, and for the first time a plan was prepared for the defense of the area. The batteries on the reef islands were re-established in better positions on the chief islands, and a few additional coastal defense guns of 120 mm. and 155 mm. calibre were brought in. Light and heavy machine guns and rocket launchers were also introduced, and slow landing craft each equipped with two torpedoes were stationed as torpedo boats on Moen, Uman, and Tol Islands. Detector coils and mines were placed along reef passes.
But the full supply of equipment which the Imperial General Staff finally ordered sent to Truk never arrived. For American submarines which patrolled the area found the Japanese transports sitting ducks for their deadly torpedoes, and Old Man Neptune claimed a share almost equal to that which he relinquished to the forces on Truk.
For its aircraft Truk had four airfields, two on Moen Island and one each on Param and Eten. Moen No. 1 included a 1,200-meter runway of thick concrete and about eighty buildings, and was one of the most important fields in the area. Moen No. 2, a "single 1,000 meter strip, was not too good, and was composed chiefly of some concrete and twice as much crushed rock. Param’s runway was originally 1,200 meters, but was later lengthened to 1,430 meters in order to serve the needs of much larger planes. Perhaps the best strip was that on Eten, which was well-surfaced, included a circular taxi loop, and which was provided with a modern, reinforced administration building.
In spite of Truk’s airfields, however, Truk’s air defense was so weak that even the Japanese regarded it as inadequate, and the condition of aircraft readiness was nothing short of disgraceful. Indeed, conditions were so bad that, according to one officer, it was ultimately necessary to beat pilots too complacent about orders to take off. Under ordinary circumstances, however, four land planes were sent up at dawn daily, although the seaplane unit chose to do almost nothing at all until after the American naval strike against Truk in February, 1944. For night fighters the Japanese depended upon a limited number of Irvings without radar and with a fixed machine gun mounted behind the pilot at an elevation of 30°. Other fighters were equipped with mechanical time bombs for air-to-air combat against B-24’s, but this method of attack, reported originally by the Japanese to be thirty per cent effective, proved completely unreliable.
Incredibly enough, however, no real offensive flight was ever launched from Truk, although Rear Admiral Sumikawa, Chief of Staff to the Commander, Fourth Fleet, was of the opinion that it was one of six planes which took off from Param Field which damaged the Intrepid during our February, 1944, naval strike against Truk. Other officers who had been stationed at Truk, however, insisted that the six planes were either from Tinian or Rabaul, and since Rear Admiral Sumikawa was in Tokyo trying to get additional material for Truk at that time, it may well be that he was wrong. In June, 1945, one air offensive from Truk was planned, but it was eventually cancelled. Moreover, even the ultimate Japanese intention of using Param Field as a base for kamikaze drives against ships at Ulithi was thwarted by the constant pounding of the field, which made it largely inoperational. The Japanese did at least manage, however, to fly routine scouting missions from Truk until the early summer of 1944, and during 1945 a few reconnaissance missions were allegedly flown to such places as Eniwetok, Guam, and Ulithi.
The efforts on the part of the Japanese Navy to convert Truk into at least a limited submarine base were equally ineffective. Prior to the war, the Japanese had made use of Kwajalein as a submarine base, but in June, 1942, a month after the organization of the Sixth Submarine Fleet, it was decided that Truk should be prepared to service submarines (though not to repair them), and a servicing base employing 130 men was set up on Dublon Island.
No submarine pens were established, however, and for protection against enemy air attack the submarines—many of them quite large—were to submerge and lie on the bottom. Actually, however, the unusual effectiveness of American undersea craft in destroying Japanese shipping and in cutting off fuel supplies so seriously hurt Japan that Japanese submarine operations at Truk never amounted to anything of significance. Even before the Sixth Submarine Fleet was compelled to move to Saipan in the spring of 1944, the Japanese at Truk had ceased their long range patrols, and they did not resume activity again until the early summer of 1944, when the six submarines of the Seventh Submarine Flotilla were ordered to Truk from Rabaul. These submarines carried out observations of Ulithi for a brief period of time until the dissolution of the Seventh Flotilla was effected in September, 1944.
Rear Admiral Sumikawa’s Report of Truk’s Air Strength At Significant Periods During the War
Airfields | 16 Feb. 1944—Prior to carrier attack 16-17 Feb | 31 March 1944— | 29 April 1944—Prior to carrier attack 29-30 April | 13 June 1944—Prior to battle for Marianas | July 1944—Aug. 1945 |
Moen No. 1 | 28 Kate | 5 Judy 12 | 6 Betty | 6 Betty | 6 Judy 12 |
Moen No. 2 | 6 Jake |
|
| 2 Judy 12 |
|
Eten | 30 Zeke | 10 Irving 11 | 10 Irving | 5 Irving 11 | 1 Irving 11 |
Param | 30 Kate | 36 Judy 12 | 12 Judy 12 | 26 Kate |
|
Dublon | 7 Rufe 11 |
| 8 Observation |
| 2 Pete 11 |
Miscellaneous | 200 (mostly fighters) | 3 Myrt 11 |
|
|
|
Total | 365 | 161 | 104 | 59 | 35 |
This, then, was largely the condition of Truk at the time the two Marine PB4Y’s appeared over the base. Only one final joker remained—and that involved the command of Truk’s forces, as curious and complex an affair as any which could possibly be devised even by the Japanese themselves. For the system at Truk provided that the Commander, Fourth Fleet, be in charge of defense against sea and air attack, but that the Army be responsible for defense measures against a land invasion. The Commander, Fourth Fleet, however, was to direct the Army’s anti-aircraft batteries, since air defense was his domain. Presumably, of course, Admiral Koga, CinC Combined Fleet, could assume charge under certain circumstances, but the precise command relationships were never made clear even to the Japanese, and it may well be that in typical Oriental fashion the terms were deliberately left vague as a sop to hypersensitive Army and Navy authorities. But the Navy itself climaxed the entire matter with its own peculiar division of command that somehow made an admiral at Palau responsible for the 26th Air Flotilla at Truk.
The first large detachment of Army troops moved into Truk in January, 1944, taking up quarters in schools and in any other houses they could find, since no barracks had been provided for Army use. The second large group, which had been hastily shipped out of Ujina, Japan, arrived shortly after the February carrier strike and only after it had lost considerable equipment during a submarine attack en route. During the next few months various other small units staggered in gradually—sometimes wet, sometimes dry. But never having heard the admonition to “bring your own ducks,” they waited for a Navy handout of everything from clothing to building supplies, then discovered that there was a war going on. Practically the only thing that the Japanese Navy on Truk had received in quite some time was the Japanese Army, and now it was asked to provide supplies. They soon all learned to starve together.
In the midst of all this happiness the two Marine reconnaissance planes made their fortuitous appearance over Truk, and the effect they had upon Admiral Koga, who was playing a waiting game aboard the battleship Musashi at anchor in the lagoon, was instantaneous. Koga, who had sortied out toward Eniwetok a little earlier—and who, having discovered Admiral Spruance’s Fifth Fleet near Kwajalein, had promptly sortied right back to his sleepy lagoon at Truk—had made up his mind to die in a decisive battle against the American fleet, but according to various colleagues of his, he wanted to choose his own time and place, and Truk in February apparently was the wrong place and the wrong time.
Concluding correctly, however, that the United States Navy was now almost ready to commence operations against Truk, Admiral Koga ordered the Yamato, the Nagato, and a few other units of the Second Fleet to depart for Palau at once. Then, on 10 February, he led the Musashi and the rest of his Combined Fleet to the same safe haven. In leaving Truk at that time, Admiral Koga was motivated by two factors: one, the inability of his fleet forces to withstand an American aerial onslaught in the Truk lagoon, and two, his personal desire to prepare for “the next stage” of the war. Thus he proceeded from Palau to Japan, where he conferred with the Imperial General Staff concerning future strategic and tactical moves.[1]
Although Admiral Koga seemed certain enough of an American strike against Truk, he nevertheless was forced to leave a large amount of merchant shipping behind— chiefly because many of them had already been pounded by naval aircraft during their runs to and from Rabaul and would have taken an even greater risk at sea. Several naval vessels, of course, were forced to remain behind because of the shortage of fuel, a condition that was soon to become more and more common to Japanese ships everwhere.
But Admiral Koga had also left behind him the erroneous impression that an American strike was unlikely before 21 February (his reason for choosing that date has never been satisfactorily established), and although a Betty on a routine scouting flight only two days before the American strike materialized had failed to return to Truk, the Japanese were completely unprepared for the attack when it actually did occur on 16 February. Their unpreparedness is particularly strange in view of the fact that a Japanese radio intercept unit had already identified voice transmissions concerning American carrier operations. Apparently, however, when six scout planes sent aloft on 15 February could find nothing, the Japanese assumed that the transmissions had originated in the Kwajalein-Eniwetok area, and they immediately rescinded their alert order. In any event, when American carrier aircraft roared in over Truk at dawn on 16 February, not one Japanese fighter plane was in the air to meet them.[2]
The seventy planes launched by the five American carriers, the Bunker Hill, Enterprise, Yorktown, Essex, and Intrepid, had a field day from the very outset, for even when the Japanese ultimately did get several scores of planes off the ground, their pilots were either too inexperienced or too ineffectual to constitute much more than a nuisance. Our own fighters strafed grounded planes with deadly effect, and our torpedo bombers really ripped up the air strips on Moen, Param, and Eten with their incendiaries and fragmentation clusters. The American goal of air supremacy in the area was completely attained. Of the 365 aircraft then based at Truk, only about 100 remained serviceable after the attack. And those were of little immediate value in light of the fact that their airfields had been very seriously damaged.
Having blasted enemy air strength at Truk, American carrier planes were now free to make a series of passes at Japanese shipping strength there, and this they did with such consummate skill and determination that not one naval vessel at Truk escaped. Three light cruisers, three destroyers, one seaplane tender, and one submarine tender all were sent to the bottom, as were approximately thirty merchant ships. The rout was complete—at the slight cost to our own forces of only four planes and some damage to the Intrepid.
Vice Admiral Hara, who was sent to Truk a week later to replace Kobayashi, the scapegoat, began immediately to rebuild his defenses, but he was hampered considerably by his lack of adequate supplies and by a second American carrier attack which commenced on 29 April. The latter strike—a total of more than 2,000 sorties—knocked out ninety-three more Japanese planes, destroyed approximately 400 buildings and six hangars, and literally put an end to Truk as a naval base of any value to Japan. From then on routine land-based B-24 attacks and occasional experimental B-29 strikes kept things humming at Truk, but actually Truk had already absorbed far more punishment than it could take. By July, 1944, only thirty-five operational aircraft remained at Truk, and of this insignificant total only one-fifth were fit for service at any given time. And according to Japanese officers, the pilots themselves, who for some strange reason seemed to have had enough, were exceedingly reluctant to attack. Hara himself was as fearless as the bull he resembled, but there was no kamikaze spirit at Truk. From the very first time that it was hit, Truk remained a badly whipped garrison which had more than met its match.
Hara did, however, make one contribution to Truk’s defense: his plan for countermeasures in the event that the base be made the object of an American invasion force. Heavy weapons were placed in caves, tunnels were dug between gun positions, and tank traps and obstacles were set up where- ever possible. Both beach mines and additional naval mines were laid, and submarine and torpedo nets were installed in the vicinity of critical docks and anchorages. Hara’s plan called for troops to dig in along the chief island beaches and to fall back to strong secondary positions if necessary. Various alternate positions were prepared for all light mobile artillery, machine-guns, and light anti-tank guns. In general, the Truk garrison, which by the end of March, 1944, included more than 12,000 Army troops, was prepared to fight in the typical manner of Japanese island forces wherever there were caves and ridges.
As it turned out, however, no amphibious invasion of Truk ever developed, and ultimately both Army and Navy personnel there had almost nothing to do. They spent part of their time ducking our planes—and the rest of it growing yams.
A fluent speaker of Japanese, Mr. Vogel served during the last part of World War II in the grade of Lieutenant as Intelligence Officer on the Staff, Commander Fifth Fleet. Subsequent to the Japanese surrender he acted as interpreter at conferences with various Japanese officials. Mr. Vogel is a member of the Organized Reserve.
“THERE’LL BE NO PROMOTION...”
Contributed by LIEUTENANT COMMANDER ROY C. SMITH, III,
U. S. Naval Reserve
The late “Bones” Cogswell once told me that his father, prior to making the dash around the Horn in the old Oregon, had been notified of his promotion from Lieutenant Commander to Commander but that the commission had not arrived when the ship sailed. As it followed the Oregon around by slow mails, the senior Marine officer on board had a fine time kidding the prospective brass hat about his lack of promotion. But by the time the commission caught up with its recipient, the Marine had been ordered out to the Philippines where he finally retired and settled down.
In the middle twenties “Bones,” then a Lieutenant Commander, was ordered to Manila to take command of a tin can and his father asked him particularly to look up his old friend the Marine. On arrival in Manila “Bones” was informed that the old gentleman regularly appeared in the Army-Navy Club bar at 1700 for his afternoon ration of two fingers of good bourbon, which had not apparently affected his health although people were doubtful about his memory.
At 1700 that afternoon, “Bones” proceeded to the Club bar and identified the old Marine. Approaching him he said, “I beg your pardon, sir, but my name’s Cogswell—”
“What!” interrupted the old veteran, looking at “Bones’” sleeve, “Ain’t you been promoted yet?”
(The Proceedings will pay $5.00 for each anecdote submitted to and printed in, the Proceedings).
[1] Vice Admiral Fukudome, who was present at the conferences held in Tokyo at that time, discussed them during a post-war interrogation as follows: “The decision of primary importance made at that conference was the adoption in principle of Admiral Koga’s plan; namely, that we must absolutely hold the line of defense between the Marianas and West Carolines, and that the necessary defensive preparation for that must be completed by June. To that end it was decided to concentrate the whole of the naval strength in that region, also to bring in a new 31st Army composed of three divisions and to build necessary airfields and coastal defense works. I advanced the view that if we were to hold that line, it would be necessary to concentrate in that area not only the Navy’s air force but also the full air force of the Army. Unfortunately, my contention was not accepted by the Army, but they agreed that they would hold themselves ready to give their support when subsequent developments should make such support necessary. I left Tokyo with the request that the Army’s full air strength should also be concentrated in that area.” The Army had not supported Vice Admiral Fukudome’s plan fully for the reason that “since the Army was carrying on operations over such a wide flung front, they could not interrupt their operations on any of those fronts without seriously affecting subsequent developments. But should it develop that a decisive engagement was to take place in the Carolines and Marianas region, then they would come to the assistance with their air force. Actually, however, that assistance never came.”
[2] In spite of earlier accounts to the contrary, this fact seems to have been well established by the United States Strategic Bombing Survey. But an even more incredible fact is that the Japanese on Truk definitely had an advance radar warning of thirty minutes, but were so disorganized and so inefficient that they failed to spread the alarm in time. Param, for example, had a warning of thirty minutes, but at Moen No. 1 the alarm was sounded just as American planes appeared overhead. In addition, many Japanese pilots were on Dublon Island, whereas their planes were on Eten and Moen Islands. To add to the confusion, the telephone system proved to be no more reliable than the men who manned it.